The present invention relates to a liquid filling nozzle to be used in liquid filling machines, in particular, to a liquid filling nozzle which is capable of filling a desired amount of various kinds of liquid into a container, such as a bottle or a can, from a liquid supply tank of liquid filling machines.
In general, liquid filling nozzles allowing to fill a container with a predetermined amount of liquid were well known. For example, one of the conventional liquid filling nozzles, as shown in FIG. 1, an outer cylinder 2 is pushed upward by a rod 1 to raise to the top end of a cup 3 above the liquid surface of a tank 4. Thus, a predetermined amount of the liquid fills the cup 3. Then a table 6, on which a container 5 is place, is lifted upward so that an inner cylinder 8 moves upward with respect to the outer cylinder 2 against a coil spring 7. Therefore small holes 9 come to be placed within the cup 3, which allows the liquid of a predetermined quantity inside the cup 3 to flow into the container 5 under gravity through an elongated hole 10. While, another example of the prior art is shown in FIG. 2, in which the cup 3 is provided at the bottom of the liquid supply tank 4, and a hole 11 is normally open to keep a predetermined amount of liquid in the cup 3. In order to transfer the liquid in the cup 3 to the container 5, the table 6 is lifted upward to move the container 5 and the inner cylinder 8 in the upward direction, which, in turn, cause a valve member 12, provided integrally at the top end of the cylinder 8, to close the hole 11 while opening a hole 9. As a result, the liquid with a predetermined quantity contained in the cup 3 flows into the container 5 under gravity through the elongated hole 10 of the inner cylinder 8. In the prior art as exemplified by these two cases as shown in FIGS. 1 and 2, it is to be noted that, although it is possible to fill a container with a predetermined amount of liquid, it usually requires an exorbitant amount of time to complete the filling process because it relies on gravity to cause the liquid to flow and, moreover, it is so structured that the liquid must flow through the small hole 9 and the elongated hole 10 of the inner cylinder 8, which is also relatively narrow. In addition, if the liquid is of high viscosity, the filling time could become virtually intolerable; and, therefore, the conventional filling nozzles could not be employed in many instances.